Natural Perspectives: Highs and lows at Bolsa Chica

Lou Murray, HB Independent

Pocket Marsh at Bolsa Chica is an example of a muted tidal wetland. It was restored to partial tidal flushing as part of the 2006 restoration project. While it has more birds per acre than the fullly tidal basin, it has far fewer fish species and is considered a lower quality restoration overall compared to the full tidal basin.

Pocket Marsh at Bolsa Chica is an example of a muted tidal wetland. It was restored to partial tidal flushing as part of the 2006 restoration project. While it has more birds per acre than the fullly tidal basin, it has far fewer fish species and is considered a lower quality restoration overall compared to the full tidal basin. (Lou Murray, HB Independent)

Vic and I attended the third Bolsa Chica Science Symposium this past Saturday, where nine scientists presented the results of their research and monitoring programs conducted at Bolsa Chica. Actually, Vic did more than attend. He was the moderator. About 80 people were in attendance.

Bob Hoffman of the National Marine Fisheries Service led off with a review of the process and costs of the 2006 restoration project that brought ocean water back to the former oil fields. He showed a photo of himself taken in 1976, when he began work at Bolsa Chica. At that time, he was told by his boss that he would retire on the Bolsa Chica project. He laughed at the idea at the time. But he'll be retiring this December and is still working on Bolsa Chica.

Because the last major dry segment won't be opened to full tidal flushing until the oil is all pumped out, the final restoration step is still many years in the future. Meanwhile, that area provides a salt panne and seasonal ponds where birds can rest, feed and even nest. The full tidal basin was created larger than needed so that there would be enough flow to serve that area when the oil wells are removed.

Hoffman pointed out that monitoring has shown that there are far more fish species utilizing the full tidal basin than the muted tidal cells, showing once again the wisdom of restoring the Bolsa Chica to a mainly full tidal versus an all-muted tidal system.

But Hoffman also had some bad news. The total project cost was $147 million, with $15 million set aside as an operations and maintenance endowment. But because cleanup of contaminants during the restoration process cost more than anticipated and because endowments earn very little interest these days, the fund has dipped dangerously low.

The full tidal basin needs to be dredged every two to three years because sand builds up at the entrance. In a system where streams flow into an estuary, storms will flush out the sand during years of heavy rains. But the full tidal basin was designed not to accept water from the Wintersburg Flood Control Channel. That water is urban runoff; no one wanted it to empty into the ocean at the clean Bolsa Chica State Beach. The alternative is periodic dredging.

Dredging operations cost about $3 million each time they are done. Because the endowment is not being replenished thanks to our tanked economy, there is only enough money left for two or three more dredgings. After that, either the Bolsa Chica will close off and become a stagnant lagoon, or other funding will need to be found. A third alternative is a lower-cost method of removing the sand.

Hoffman discussed one concept that might offer a lower-cost way to move the sand. A system of pipes and pumps could be installed that would agitate the sand on the bottom of the bay just at the time of outgoing tide, so that the tide would carry the sand out to the beach.

Rachel Woodfield of Merkel & Associates presented an update on the biological monitoring being done in the lowlands. The researchers monitored bird use of the newly restored areas in years two, three and five post-restoration. They will continue these studies until 2016, which is 10 years after the new bay was opened to tidal flushing.

They found an average of 9,900 birds at each survey, with 160 species observed over the past five years. As expected, Western sandpipers were the most abundant species, followed by black-bellied plovers. The full tidal basin had the most birds, but the Pocket Marsh, a muted tidal system, had the highest density of birds per acre.

Surprisingly, endangered Belding's savannah sparrows were in the top 10 most abundant birds. That is terrific news because there had been concern that loss of pickleweed acreage with conversion to deepwater habitat might lower the numbers of those birds. The restoration project was designed, however, to improve the quality of the pickleweed habitat with muted tidal flushing. They had hoped that this would provide better habitat so that the bird density per acre could be higher.

The good news is that the number of Belding's savannah sparrows using the lowlands in the newly restored area has increased, not decreased. Prior to restoration, there had been between 143 and 196 territories in use. Each territory represents a breeding pair of sparrows. After restoration, there were 269 breeding pairs in 2009 and 261 this summer. That represents a significant increase in the number of pairs that are able to nest in the habitat.

Merkel's researchers also conducted fish and invertebrate monitoring studies. They used a variety of sampling methods and have found 60 species of fish to date in the full tidal basin. In contrast, only 12 species are using the muted tidal cells. This underscores the wisdom of restoring Bolsa Chica to full tidal flushing.

This summer, there were lots of anchovies in the full tidal basin, as well as grunion, topsmelt and killifish. Some of the odder-looking species that they found were shovel-nosed guitarfish, thornback rays and butterfly rays. They also found a 33-pound halibut and dozens of baby diamond turbot no bigger than quarters.

Part of the restoration included planting 0.9 acres of eelgrass in the full tidal basin. That plant has now spread throughout the basin, covers about 50 acres and provides good habitat for fish. Almost all of the fish species were represented by juveniles, indicating that the basin is serving as a spawning ground and nursery, as intended.

One of the exciting finds in their studies of invertebrates was a burrowing crab. This species (Malacoplax californiensis) is nearly extinct, according to Woodward. The crab is covered with what looks like fur, making it a very odd animal indeed. It's always good to find rare species living at Bolsa Chica.

Woodward underscored that the high diversity of bird, fish and invertebrate species and their abundant usage of habitat are dependent upon keeping the new ocean inlet at Bolsa Chica open. Somehow, we as a community will need to find a will and a way to do that.

VIC LEIPZIG and LOU MURRAY are Huntington Beach residents and environmentalists. They can be reached at LMurrayPhD@gmail.com.